diff --git a/test/shell/lvmetad-pvscan-cache.sh b/test/shell/lvmetad-pvscan-cache.sh
index 22c9b5e16..501eec510 100644
--- a/test/shell/lvmetad-pvscan-cache.sh
+++ b/test/shell/lvmetad-pvscan-cache.sh
@@ -32,7 +32,7 @@ vgs | grep $vg1
 pvchange --metadataignore y "$dev1"
 aux disable_dev "$dev2"
 pvscan --cache
-check pv_field "$dev1" vg_name ""
+check pv_field "$dev1" vg_name "[unknown]"
 aux enable_dev "$dev2"
 pvscan --cache
 check pv_field "$dev1" vg_name "$vg1"